Perfusion imaging with arterial spin labeling in acute encephalopathy with reduced subcortical diffusion following secondary generalized status epilepticus

Abstract

Magnetic resonance perfusion imaging with arterial spin labeling (ASL) can provide valuable information on the circulatory changes associated with status epilepticus (SE). We report a case of a girl with an old brain abscess in the right frontal lobe who developed secondary generalized SE twice (at 3 and 4 years of age). Although she made a full recovery after the first SE, she developed acute encephalopathy with reduced subcortical diffusion (AED) following the second SE with a monophasic clinical course. We compared the ASL findings on day 4 after onset of each SE. After the first SE, ASL revealed postictal hypoperfusion in bilateral anterior circulation territories. By contrast, after the second SE, there was a marked increase in ASL signals of the entire cortex, particularly in the right fronto-parietal lobe, which corresponded to the area of reduced subcortical diffusion. Prolonged cortical hyperperfusion may have caused relative ischemia of the subcortex. As there is growing evidence that oligodendrocytes are selectively vulnerable to ischemia via glutamatemediated excitotoxicity, our findings suggest that white matter ischemia may cause axonal injury in this case. Finding of prolonged cortical ASL hyperperfusion around day 4 after SE onset may be important for the detection of reduced subcortical diffusion.

Hemodynamic state of periictal hyperperfusion revealed by arterial spin-labeling perfusion MR images with dual postlabeling delay

“…MRI was performed using a 3-T scanner (HDxt Signa; GE Healthcare, Milwaukee, WI) equipped with an 8-channel receive-only head coil for signal reception. The ASL was prepared using a 3-dimensional spiral fast-spin echo sequence with background suppression for perfusion imaging covering the entire brain, as previously described [ 5 , 7 , 8 , 12 , 15 , 17 , 18 , 20 ]. A pulsed continuous protocol was employed.…”

“…Subsequent routine EEG recordings were obtained from an 18-channel digital EEG machine (Neurofax; Nihon-Kohden, Tokyo, Japan) with electrode placement according to the International EEG 10–20 system, as described previously [ 5 , 7 , 8 , 12 , 20 ]. Evaluation of the EEG findings was also based on visual inspection by two board certified electroencephalographers (T.M.…”

“…Arterial spin labeling (ASL) is a completely non-invasive and repeatable perfusion magnetic resonance image that uses magnetically-labeled water in the blood as an endogenous tracer. Recent studies have demonstrated that combined use of a perfusion image with ASL and diffusion-weighted imaging (DWI) can provide valuable information on the circulatory and metabolic consequences associated with epilepsy during ictal [ [1] , [2] , [3] , [4] , [5] , [6] , [7] ] or periictal (or postictal) periods [ 2 , [8] , [9] , [10] , [11] , [12] ].…”